| 摘要 |
PROBLEM TO BE SOLVED: To provide a pressurizing pump device reduced in device size, a liquid injection apparatus, and a method of canceling the pressurization of a pressurized fluid. SOLUTION: In an off-carriage type printing apparatus, when a pump motor 28 is forwardly rotated to feed the pressurized air to an ink cartridge, its rotation is converted into the reciprocating linear motion of a pressing member 39 by a cam mechanism 33 to repeat the extending/retracting operations of a diaphragm 37 for pressurizing operation. On the other hand, the pressure value of the pressurized air is calculated according to the detected value of a pressure sensor 21. When the pressure value of the pressurized air becomes a prescribed threshold or higher, the pressurization is canceled. Namely, the pump motor 28 starts to rotate reversely, a driven part 52 is rotated by a friction clutch mechanism 48 in the arrow direction of E in the figure, and the push-in part 52b of the driven part 52 is brought into contact with the valve opening lever 55 of an atmosphere releasing valve 22. In this case, the valve opening lever 55 is swung to brought a valve hole in an open state to keep the atmosphere releasing valve 22 in an open state so as to release the pressurized air to the outside. COPYRIGHT: (C)2006,JPO&NCIPI |
